他正要睡觉,电话铃响了 用英语怎么说 He ( ) ( ) ( ),when the telephone rang .

问题描述:

他正要睡觉,电话铃响了 用英语怎么说 He ( ) ( ) ( ),when the telephone rang .

He ( was ) (to ) (sleep ),when the telephone rang .
be to do表示正要,有将来的意思